判断是否按下某键

第一种，检测键盘状态

hThread=CreateThread(NULL,0,(LPTHREAD_START_ROUTINE)MyHokey,NULL,0,&ThreadID);
////////////////////////////////////////////////////////////////////////////////////////////////////
DWORD WINAPI MyHokey (LPVOID pParam)
{
Tloop:
    if(GetKeyState(VK_F1)<0)
    {
        Sleep(100);
    }
    if(GetKeyState(VK_F2)<0)
    {
        Sleep(100);
    }
    if(GetKeyState(VK_F3)<0)
    {
        Sleep(100);
    }
    if(GetKeyState(VK_F4)<0)
    {
        Sleep(100);
    }
    if(GetKeyState(VK_F5)<0)
    {
        Sleep(100);
    }
    if(GetKeyState(VK_F6)<0)
    {
        Sleep(100);
    }
    if(GetKeyState(VK_F7)<0)
    {
        Sleep(100);
    }
    if(GetKeyState(VK_F8)<0)
    {
        Sleep(100);
    }
    Sleep(50);
    __asm jmp Tloop
    return 0;
}

第二种键盘Hook

以修改标题为例

/////////////////////////////////////////////////////////////////////////////
#define WH_KEYBOARD_LL     13

typedef struct tagKBDLLHOOKSTRUCT {
    
    DWORD   vkCode;
    
    DWORD   scanCode;
    
    DWORD   flags;
    
    DWORD   time;
    
    DWORD   dwExtraInfo;
    
} KBDLLHOOKSTRUCT, FAR *LPKBDLLHOOKSTRUCT, *PKBDLLHOOKSTRUCT;

int MyCount = 0;
LRESULT CALLBACK KeyboardProc(
                              int code,       // hook code
                              WPARAM wParam,  // virtual-key code
                              LPARAM lParam   // keystroke-message information
                              )
{ 
    AFX_MANAGE_STATE(AfxGetStaticModuleState());
    LPKBDLLHOOKSTRUCT pKB = (LPKBDLLHOOKSTRUCT)lParam;
    if (code == HC_ACTION)
    {
        if ((pKB->vkCode == VK_F4))
        {
            if (GetKeyState(VK_F4)<0)
            {
                MyCount ++;
                CString check;
                check.Format("按下F4次数为： %d",MyCount);
                AfxGetMainWnd()->SetWindowText(check);
            }
        }
    }
    return  CallNextHookEx(0,code,wParam,lParam);
}

void CMyForm::OnButton1() //快捷键测试
{
    HHOOK IsHook= ::SetWindowsHookEx(WH_KEYBOARD_LL, KeyboardProc,AfxGetApp()->m_hInstance, 0);
    if (IsHook == 0)
    {
        AfxMessageBox("error003");
    }
}